A few hours before President Obama delivers his State of the Union address Tuesday night, the state of America's terrorist detention policy will be laid bare in a Manhattan courtroom. Ahmed Ghailani, charged with 285 counts in the bombings of our embassies in Kenya and Tanzania, will be sentenced for one count of "destruction of government property." Ghailani's lawyers tried to get even this lone charge dismissed, calling it a "manifest injustice." Judge Lewis Kaplan rejected their motion last week, declaring: "If there was any injustice in the jury's verdict, the victims were the United States and those killed, injured, and otherwise devastated by these barbaric acts of terror." Amen to that.

Obama probably won't mention Ghailani's name from the rostrum of the House of Representatives. But the Ghailani case underscores the necessity of his quiet decision to change course and lift the ban he imposed after his inauguration on new military commission trials at Guantanamo. An infuriating New York Times story last week described how Ghailani's lawyers managed to convince the jury that their client had no idea that he was involved in a plot to blow up two American embassies using explosives-laden trucks. The jury even sent a note asking the judge whether Ghailani needed to know the plot's specific objectives, or was it enough that he knew something unlawful was going on? The judge told them Ghailani had to know the specific objective of the conspiracies - and later that same day, the jury acquitted him on all but one count.

But Ghailani did know the specific objectives of the plot. In 2007, after being transferred from CIA custody to Guantanamo Bay, he was interviewed by the FBI and provided a confession he acknowledged was completely voluntary. Ghailani told the FBI that he had put "the pieces of the puzzle together" before the attacks and even considered stopping the plot because he believed civilian locations like embassies and hotels were not proper targets for al-Qaeda.

He said he thought about how he "would have been a hero and saved many lives" if he had warned anyone. But in the end, he did nothing - all he could think of, he said, was that "Ahmad the driver is going to die and the American Embassy was the target." Prosecutors never entered his confession into evidence, fearing it would be excluded and could open the door for defense lawyers to put the U.S. government on trial. But had the jury known about Ghailani's confession, this al-Qaeda terrorist likely would have been convicted on 285 counts, not one.

Kyndra Rotunda, a former military prosecutor at Guantanamo Bay, told me that "any good prosecutor could likely [have gotten] Ghailani's confessions made to the FBI admitted before a military commission." The law, she says, specifically allows the judge to consider the "lapse in time, change of place, or change in identity of the questioners between the statement sought to be admitted and any prior questioning of the accused." In Ghailani's case, Rotunda explained, "all three factors changed . . . in the detainee's favor." Defense lawyers would have had "an uphill battle" keeping his confession out. In other words, Ghailani would probably have been convicted for the embassy bombings in a military commission.

Though they are loath to admit it, administration officials now seem to recognize that this is the case. The decision to resume new military commissions is a good sign. But Americans are still owed answers to other questions - such as when and where Khalid Sheik Mohammed and the other Sept. 11 conspirators will be tried.

Last week, The Post reported on new evidence that KSM had indeed decapitated Wall Street Journal reporter Daniel Pearl. But the administration has been dragging its feet for months on the question of KSM's prosecution for this and other crimes. If the president wants a moment of bipartisan applause Tuesday night, he should announce that Khalid Sheik Mohammed will soon face justice before a military commission at Guantanamo Bay. Obama has recognized reality and is pivoting to the center on economic matters. He should do the same when it comes to the war on terrorism.